1. Field of the Invention
The present invention relates to a color plasma display panel (PDP), and more particularly, to a barrier in a color PDP and a method for manufacturing the same.
2. Discussion of the Related Art
FIG. 1 is a cross-sectional view showing a structure of a conventional color PDP.
Referring to FIG. 1, a color PDP includes an upper substrate and a lower substrate.
The lower substrate includes a lower glass substrate 10, a first insulating layer 11 for preventing an electrode material from penetrating into the lower glass 10 on baking, a lower electrode 12 on the first insulating layer 11, and barriers 13 for preventing crosstalk between cells adjacent to the lower electrode 12.
The upper substrate includes an upper glass substrate 15, a second insulating layer 16, a plurality of upper electrodes 17 on the second insulating layer 16, first and second dielectric layers 18 and 19 for maintaining surface charge generated in discharge of the upper electrode 17, and a protecting layer 20 for preventing damage of the first and second dielectric layers.
A luminescent material 14 is formed on the barriers 13 and over the lower glass substrate 10.
A mixed gas of argon and neon is injected to the space between the upper substrate and the lower substrate as to become non-active gas of a plasma state, thereby forming a discharge region.
A method for manufacturing a color PDP having the above-described structure will be discussed.
First, a first insulating layer 11 is formed on a transparent lower glass substrate 10 in order to prevent an electrode material from penetrating into the lower glass substrate 10 on baking.
Secondly, a lower electrode 12 is formed on the insulating layer 11 and then dried and baked. Next, after completing the drying and the baking of the lower electrode 12, a barrier material is printed over the lower glass substrate 10 about 10-13 times by a printing process in order to prevent color mixture between adjacent discharge cells, thus forming barriers 13 by drying and baking.
One of typical methods for forming barriers employs a thick film printing technique. In this method, the barriers are formed not by etching the barrier material but by printing it on a predetermined region a plurality of times. In the method of printing a thick film, utilizing a screen mask, a mixed paste mixed with ceramic powder and organic binder solvent is printed and dried 10 times and then baked at a temperature of 450-700.degree. C., thereby forming barriers. In this case, each time the barrier material is printed, the barriers grow 13-15 .mu.m thick. Thus, the total thickness of the barrier is 130-150 .mu.m. A material for forming the barriers is an insulating paste.
Subsequently, a luminescent material is formed on the lower electrode 12 and the barriers 13, thus completing the lower substrate 12.
As for the upper substrate, on the transparent upper glass substrate 15, there is formed a second insulating layer 16 on which upper electrodes 17 are formed. At this time, the upper electrodes 17 is a transparent electrode (ITO: indium-tin oxide) which is formed by depositing indium oxide and tin-oxide. Alternatively, a stacked metal electrode composed of three layers which are chromium-copper-chromium, can be used as the transparent electrode, thus improving voltage decrease.
Next, in order to drop a driving voltage by charge generated at the interface, first and second dielectric layers 18 and 19 are formed. Then, a protecting layer 20 is formed on the second dielectric layer 19 to prevent damage of the first and second dielectric layers 18 and 19.
Thereafter, the upper and lower substrates are sealed by means of a sealant, so as to form a sealed space. Then, a discharge gas is sealed within the sealed space. A hole (not shown) made in a corner of the bottom of the sealed space is connected to a glass tube (not shown) for gas injection, so that the gas sealed within the sealed panel is taken out. When the gas is taken out, the vacuum degree is generally 10.sup.-6 -10.sup.-8 torr.
The gas is injected (about 500 torr) by means of a gas injection equipment and then the glass tube is sealed by heat, thus forming a panel which completely seals the discharge gas.
In such a conventional method for manufacturing barriers of a color plasma display, it is difficult to manufacture barriers of a desired quality by repeatedly printing a barrier material about 10 times. Further, since a baking temperature of the paste which is a barrier material is high, the upper and lower glass substrates are necessary to be annealed, or a special substrate has to be used, in order to prevent the quality decrease caused by variation of the glass dimension. Furthermore, due to limitations of the screen mask used for a printing, the barriers of the color PDP is not useful for any color PDP of a large size.